The present invention relates to a traffic crash attenuation system. More particularly, the present invention relates to a system, method and apparatus for absorbing the kinetic energy from an impacting vehicle in a controlled and safe manner with roadside safety devices such as: guardrails and median barrier end treatments, crash cushions, and truck mounted attenuators. Further, the system may utilize a trailer mounted attenuator as a portable crash cushion with hinges to allow folding of the system while in transit. Two bursting tubes may be simultaneously activated. The system provides for the controlled rupturing of a tubular member by a mandrel whereby forces of an impacting vehicle are absorbed. The present inventive system may utilize a rectangular mandrel and a corresponding rectangular tubular member.
U.S. Pat. No. 4,200,310 illustrates an energy absorbing system which utilizes a number of cylindrical energy absorbing members placed in a series-type relationship on a frame mounted to a truck. The system is provided with an alignment or guidance frame. However, there is nothing which teaches any selectively controlling the rupture of the cylindrical members via a trailer mounted, hinged portable crash cushion. The mechanism of energy dissipation is significantly different than that of the present invention.
U.S. Pat. No. 3,143,321, teaches the use of a frangible tube for energy dissipation. As with the present invention, the apparatus disclosed in U.S. Pat. No. 3,143,321 uses a mandrel receivable within a tubular member. However, there is no teaching of a means for selectively controlling the rupturing along a length of the tubular member.
Further, U.S. Pat. No. 3,916,720 discloses an energy absorbing steering column relying upon frictional forces to dissipate impact energy. U.S. Pat. No. 5,732,801 teaches the use of an energy absorbing bumper support structure having collapsing cylinders. Again, neither reference teaches the rupture of tubular absorbers within a portable, hinged structure.